Mining technology of steeply inclined coal seams with downward pseudo-inclined mining

Abstract

The present invention relates to a mining process for steeply inclined coal seams with a dip-pseudo-inclined mining method. By using the retreat mining method, a coal mining face is arranged between the return airway and the conveyor gateway. A shearer is arranged to travel and cut coal on the coal mining face, and support facilities are set up on the coal mining face. When the true dip angle of the coal seam is more than 70° and the average inclined length is more than 100 meters for steeply inclined coal seams, the upper outlet of the coal mining face arranged in the coal seam is 15 - 20 mm ahead of the lower outlet, so that the pseudo-dip angle of the coal mining face is 58° - 62°. Due to the dip-pseudo-inclined angle of the coal mining face in the present invention, flying gangue and channeling gangue are not easily introduced into the operation area, reducing the impact force of flying gangue and channeling gangue, minimizing the safety threat of flying gangue and channeling gangue to operating personnel, and improving the coal mining efficiency and safety effect of the coal mining face.

Description

Technical Field

[0001] The invention relates to an underground coal mining method, in particular to a steeply inclined coal seam downward-sloping mining process. Background Art

[0002] The reserves of steeply inclined coal seams account for 40% of the total coal reserves in my country, and 80% of the southern mining areas have steeply inclined coal seams. So far, the mining methods of steeply inclined and extremely thin coal seams are mainly classified by support form: the first is the pseudo-inclined constant wall segmented intensive mining method, which adopts the method of blasting coal and single hydraulic support support. This method has extremely low production efficiency, poor safety guarantee, and high labor intensity for workers; the loss of segmented coal pillars is large, accounting for about 15% of the coal volume in the section; the "triangle area" below the dense segmented trend is poorly ventilated and easy to accumulate gas; the second is the flexible shield support mining method, which requires the coal seam to be relatively stable; the inclination angle is large; the labor intensity of disassembling and assembling the support is large; the support isolates the working space from the goaf, and the gangue cannot be removed during the mining process; the above-mentioned steeply inclined and extremely thin coal seam mining methods cannot achieve efficient mining, and safety cannot be fundamentally guaranteed. In order to achieve sustainable development of mines and make full use of coal resources, it is necessary to improve the pseudo-inclined mining process technology of steeply inclined coal seams. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a steeply inclined coal seam downward pseudo-inclined mining process.

[0004] The coal mining process of the present invention is to set a return air lane and a machine lane with a horizontal position lower than the return air lane in the coal seam, and adopt a return mining method, arrange a coal mining working face between the return air lane and the machine lane, arrange a coal mining machine on the coal mining working face to walk and cut coal, and set support facilities on the coal mining working face.

[0005] The coal mining face has an upper outlet close to the return air lane and a lower outlet close to the machine lane.

[0006] Specifically: when the true inclination of the coal seam is above 70° and the average inclination length is above 100 meters, the upper outlet of the coal mining face arranged in the coal seam is 15-20mm ahead of the lower outlet, so that the pseudo inclination of the coal mining face is 58°-62°.

[0007] In the above-mentioned steeply inclined coal seam downward pseudo-inclined mining process, the method of walking and cutting coal by arranging the coal mining machine on the coal mining working face is as follows:

[0008] A feed section is provided at the upper outlet, and the feed section is arranged obliquely with the coal mining working face to form an angle of less than 8°; the coal mining machine gradually cuts into the coal wall when it moves, completing the feed; the first coal cutting is 0.8m;

[0009] After the feed is completed, cut coal downward to the lower outlet at a downward speed not greater than 3 m / min.

[0010] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the length of the feed section is 25 m - 30 m.

[0011] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the support strength of the support facilities is greater than 280 kN / m².

[0012] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the support facilities include hydraulic supports with a support strength greater than 386 kN / m²; the roof of the hydraulic support is parallel to the roof of the coal mining face, the center line of the hydraulic support is parallel to the return air roadway and the machine roadway, and the center line of the hydraulic support forms an angle of 78 - 72° with the coal mining face.

[0013] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the hydraulic support advances continuously along the strike of the coal mining face as the mining progresses, controlling the roof of the mining section. Its maximum roof control distance is 5.64 m, the minimum roof control distance is 4.84 m, and the roof caving step distance is 0.8 m;

[0014] The hydraulic support pushes the conveyor. When pushing in each coal mining cycle, first push the hydraulic support at the lower end of the coal mining face and gradually move upward to push the remaining hydraulic supports;

[0015] The gob area after the coal mining face is pushed is treated by the full caving method.

[0016] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the length of the section without hydraulic props at the upper outlet of the coal mining face shall not be greater than 1.5 m. When it is greater than 1.5 m, immediately add hydraulic supports; the length of the section without hydraulic props at the lower outlet shall not be greater than 1.5 m. When it is greater than 1.5 m, lower the hydraulic supports downward;

[0017] The section without hydraulic props at the lower outlet is supported by single hydraulic props with caps. The row spacing of the single hydraulic props is 0.8 m, the column spacing is 0.8 m, and its roof control distance is between 4.34 m and 5.14 m, and the roof caving step distance is 0.8 m.

[0018] The mining technology of steeply inclined coal seams with a downward pseudo-inclined mining method as described above, wherein the pedestrian safety exit section at the lower outlet is supported by single hydraulic props with wooden planks. Among them, the specifications of the wooden planks are: length 200 mm, width 100 mm, thickness 50 mm;

[0019] Among them, the density of the single hydraulic props is not less than 0.8 props / m², the row spacing of the single hydraulic props is 0.8 m, and the column spacing is 0.8 m.

[0020] The mining technology of steeply inclined coal seams with downward pseudo-inclined mining as described above, wherein, a row of inclined dense props is arranged on the side close to the coal wall in the pedestrian safety exit section at the lower exit, and the prop spacing of the inclined dense props is 400 mm; a row of strike props is driven at the top beam of the first support in the pedestrian safety exit section at the lower exit, and the prop spacing is 400 mm.

[0021] The mining technology of steeply inclined coal seams with downward pseudo-inclined mining as described above, wherein, after the coal mining face is advanced, when the support facilities are withdrawn, the strike props are withdrawn first, and then the inclined dense props are withdrawn. Replacement props are driven before the inclined dense props are withdrawn.

[0022] Beneficial technical effects:

[0023] Through more than 7 months of verification mining, as the angle of the coal mining face becomes gentler (reducing the dip angle of the coal mining face), no phenomenon of support collapse or sliding has occurred in this verification mining coal mining face, and the operation risk of the operators has also been reduced accordingly. Due to the downward pseudo-inclined angle of the coal mining face, flying gangue and channeling gangue are not easily introduced into the operation area, reducing the impact force of flying gangue and channeling gangue, and reducing the safety threat of flying gangue and channeling gangue to the operators. Since the downward pseudo-inclined mining was adopted in the work, no accident of personnel injury caused by flying gangue and channeling gangue has occurred in this coal mining face, effectively ensuring the safety of the operators and improving the recovery efficiency and safety effect of the coal mining face.

[0024] There is an obvious change in the mining difficulty, the monthly average output is significantly increased, the equipment failure rate is greatly reduced, and the safety effect is obvious. According to the statistics of uncertain data, since the coal mining face was adjusted to downward pseudo-inclined mining, it has reduced the investment of the mine by nearly ten million yuan.

[0025] Through verification mining, multiple steeply inclined coal mining faces such as 0.6 - 0.8 m thin coal seams and 1.15 - 1.45 m medium-thick coal seams have been safely mined. The production task has been exceeded for each face. Compared with the previous true inclined upward pseudo-inclined fully mechanized mining, the per capita output per face has increased by 25%, the labor efficiency per ton of coal has increased by 31%, the coal recovery rate has increased by 25%, and no safety accidents such as flying gangue injuring people in the steeply inclined coal mining face have occurred.

[0026] By adjusting the downward pseudo-inclined angle of the coal mining face and the support layout angle, the rectification time of the coal mining face due to support collapse, sliding, and shearer overturning has been reduced, providing sufficient time for the coal mining face to be mined and ensuring the advancement of the coal mining face. Brief description of the drawings

[0027] Figure 1 It is a schematic layout diagram of the coal mining face of the present invention.

[0028] Figure 2 It is a schematic layout diagram of the hydraulic support of the present invention, and a schematic diagram of the process of cutting and pushing the conveyor; Figure 2 (a) is the layout method of the hydraulic support;Figure 2 (b) is the bending section of the conveyor; Figure 2 (c) The shearer enters the bending section of the conveyor; Figure 2 (d) The shearer passes through the bending section of the conveyor; Figure 2 (e) The shearer moves upward to complete the knifing. Specific implementation manner

[0029] Example 1:

[0030] The present invention can be arranged in steeply inclined coal seams under the following conditions, and of course it is not limited to being arranged in the following coal seams.

[0031] Basic situation of the verified mining coal mining face: The average strike length of the coal mining face is 750 m, the average dip length is 120 m, the average coal seam thickness is 1.45 m, the coal seam dip angle exceeds 70°, and the average inclined area of the coal seam is 99442 m². The coal mining face adopts the retreating single-strike longwall mining method and uses fully mechanized coal mining. To improve the resource recovery rate, the roadway along the goaf is protected and mined without coal pillars.

[0032] The roadway along the goaf is used for ventilation, pedestrian passage, coal transportation, material transportation and storage. Support method for the roadway along the goaf: The roof and both sides are permanently supported by resin bolts with ribbed steel bars and T-shaped steel strips, anchor cables, and wire meshes (the coal part of the roof does not use T-shaped steel strips, only resin bolts and wire meshes are used), and the roof is reinforced by steel strand anchor cables with a length of 5180 mm and a diameter of Ф = 17.8 mm (when two rows of bolts are used for support, the resin bolts at the position close to the coal seam and the arch part of the right side can be replaced). The roof bolts are supported by resin bolts with ribbed steel bars with a length of L = 1800 mm and a diameter of φ = 18 mm. 300 mm below the high side of the roadway coal seam is supported by steel strand anchor cables with a length of 3180 mm and a diameter of Ф = 17.8 mm, and the sides are locked along the roadway with flat iron strips.

[0033] The return airway is used for ventilation, pedestrian passage, material and equipment transportation.

[0034] The diameter of the shearer drum arranged on the coal mining face is 1.4 m; the applicable mining height is 1.6 - 2.5 m; the drum cutting depth is 0.8 m; the walking speed is 0 - 4.0 m / min. The coal mining face uses an MG250 / 710-AWD3 spiral double-drum shearer to cut coal downward with a cutting depth of 0.8 m.

[0035] The support height of the hydraulic support is 1.4 - 3.2 m, the support width is 1.43 - 1.60 m; the initial support force is 1538 kN - 2561 kN; the support strength is 0.38 Mpa - 0.47 Mpa. The coal mining face uses a ZY3200 / 14 / 32Q type steeply inclined shield hydraulic support

[0036] The coal mining face uses a scraper conveyor to transport coal into the roadway along the goaf

[0037] Example 2:

[0038] Reference Figure 1 , the false dip arrangement of the coal mining face.

[0039] The dip angle of the coal seam directly affects the self-sliding effect of the coal. The natural angle of repose of the coal is generally 45°. The larger the angle, the more conducive to the self-sliding of the coal, but it also increases the conversion efficiency of the potential energy of the coal and rock blocks into kinetic energy, making the rolling coal and rock blocks too fast, causing damage to the equipment below the coal mining face, and flying into the working area will also pose a great threat to the safety of personnel. If the dip angle of the coal seam is too small, the self-flow speed is slow, affecting the mining efficiency and coal recovery. If the dip angle is too large, there will be potential safety hazards.

[0040] Reference Figure 1 , in the figure, OC is the coal mining face arranged with false dip, β = ∠OBA is the true dip angle of the inclined coal seam OBC in the steeply inclined coal seam, and βˊ = ∠OCA is the false dip angle of the coal mining face. The relationship between the two is related to the dip angle δ.

[0041] To meet the requirement that the false dip angle βˊ of the coal mining face forms 58° - 62° during coal seam mining, from the formula:

[0042] sinβˊ = sinβ × sinδ calculation,

[0043] It can be known that the dip angle of the coal seam is:

[0044]

[0045] Arranged according to the dip angle of 78 - 72°, the false dip angle βˊ of the coal mining face can be formed at 58° - 62°. Through the ground model experiment, it is found that when the false dip angle of the coal mining face is 58° - 62°, the distance of the return airway ahead of the machine roadway is 15m - 20m, the dip angle of the coal seam is 78° - 82°, and the false dip angle of the coal mining face decreases from 70° to about 58° - 62°. The false dip angle of the coal mining face becomes significantly gentler, enabling the shearer to overcome the phenomenon of machine reversal, and it is not easy for flying gangue and running gangue to enter the working area. However, due to the too large false dip angle of the coal mining face and the too large end face distance of the support, an effective support must be established for the roof of the coal mining face, otherwise it is easy to cause roof collapse, resulting in the blockage of the coal cutting roadway, and the falling gangue will damage the equipment.

[0046] Example 3:

[0047] Coal mining process sequence: coal cutting preparation, the shearer cuts coal downward, the hydraulic support is pushed (the hydraulic supports approach the coal wall alternately, while the conveyor remains stationary. It is equivalent to pulling the hydraulic support by the conveyor through the connection between the hydraulic support and the conveyor), the shearer travels upward without load, collects floating coal, pushes the conveyor (equivalent to pushing the conveyor by the hydraulic support through the connection between the hydraulic support and the conveyor), and cuts the coal. This is one coal mining cycle.

[0048] The shearer is a spiral double-drum shearer, cutting coal downward to drop coal.

[0049] The coal loading method is that the spiral double drums of the shearer cooperate with the coal shoveling plate of the scraper conveyor to load coal.

[0050] The coal transportation method is that in the coal mining face, coal slides by itself to the bridge-type transfer machine in the roadway.

[0051] An approach cut section is set at the upper outlet. The shearer uses the end oblique cutting method for approach cutting. The length of the approach cut section is not less than 28 m. The approach cut section is arranged obliquely with the coal mining face, forming an angle less than 8°. When the shearer travels, it gradually cuts into the coal wall to complete the approach cut. The first cut of coal is 0.8 m.

[0052] After completing the approach cut, cut coal downward to the lower outlet, and the downward speed is not greater than 3 m / minute. After cutting coal is completed, return empty and travel upward. The maximum upward speed of the shearer is ≤2 m / minute.

[0053] Determination of the length of the approach cut section: D = Lmining + Lbending of conveyor = 13 + 15 = 28 m

[0054] In the formula: D—the length of the approach cut section, m;

[0055] Lmining—the length of the shearer body, the maximum length is 13 m;

[0056] Lbending of conveyor—the length of the bending section of the conveyor, taking 15 m;

[0057] The approach cut distance is taken as 28 m.

[0058] Example 4:

[0059] Support facilities are set in the coal mining face.

[0060] The support strength of the support facilities is greater than 280 kN / m2. In this example, 283 kN / m2 is taken, based on the following:

[0061] Calculate the reasonable support strength of the coal mining face as:

[0062] pt = 9.81hγk = 9.81×2.0×2.4×6≈283 kN / m2

[0063] In the formula: Pt is the reasonable support strength of the coal mining face, kN / m2;

[0064] h is the mining height, taking the maximum mining height of 2.0 (m);

[0065] γ is the gravity density of the roof rock, 2.4 t / m3;

[0066] k is the ratio of the thickness of the overlying strata that should be supported by the props in the coal mining face to the mining height, generally taking a value of 4 - 8.

[0067] Under the requirements of the above reasonable support strength, according to the conditions of the coal seam roof and floor, the coal seam situation, and the mining height situation in the coal mining face, the ZY3200 / 14 / 32Q type hydraulic support is selected. Calculated according to the working resistance of the hydraulic support of 3200 kN, the support strength of this support is:

[0068]

[0069] The minimum support strength of the support is 386 kN / m², which is greater than the weighting strength of 283 kN / m² of the roof in the coal mining face.

[0070] Roof control technology in the coal mining face:

[0071] In the coal mining face, the roof is supported by following the shearer to pull the supports. The hydraulic supports are continuously advanced forward along the strike of the coal mining face as the coal is mined, controlling the roof in the mining section. The maximum caving distance is 5.64 m, the minimum caving distance is 4.84 m, and the caving step distance is 0.8 m; the goaf after the coal mining face is pushed through is treated by the full caving method.

[0072] Reference Figure 2 (a), the roof or floor of the hydraulic support 6 is a plane, the center line 61 of the hydraulic support is parallel to the length direction of this plane, and the coal mining face is arranged in the coal seam 1. After the hydraulic support is lowered to the coal mining face, adjust the attitude of the hydraulic support so that the roof of the hydraulic support is parallel to the roof of the coal mining face, and the center line of the hydraulic support is parallel to the return airway 2 and the machine roadway 3. The angle formed by the center line of the hydraulic support and the coal mining face is 78 - 72°. For this reason, the shearer 4 cuts coal downward, and after the coal cutting is completed, it returns empty and goes upward, and picks up the floating coal when returning empty and going upward (the cut coal is picked up onto the conveyor by the rotation of the drum 5). The shearer 4 goes upward to the upper outlet to pick up all the floating coal. Then, except for multiple hydraulic supports at the upper outlet, the remaining hydraulic supports of the entire coal mining face start to push the conveyor 7 towards the coal wall, and the pushing direction is parallel to the strike of the return airway and the machine roadway (the direction forming an angle of 78 - 72° with the coal mining face); since multiple hydraulic supports at the upper outlet have not pushed the conveyor 7 yet, a 15 m bending section of the conveyor is formed here. Reference Figure 2 (b); then the shearer goes downward and when it enters the bending section, the drum 5 cuts into the coal wall 8 and enters the section of the conveyor that has been pushed to the coal wall. Reference Figure 2 (c), the drum penetrates into the coal wall 8; then multiple hydraulic supports at the upper outlet start to push the conveyor towards the coal wall again, making the conveyor of the entire coal mining face parallel to the coal mining face (coal wall) and pulled into a straight line. Reference Figure 2 (d); the shearer goes upward again and cuts the coal at the upper outlet. Reference Figure 2(e); Subsequently, normal coal mining begins in the downwards direction. The center line 61 of the hydraulic support is parallel to the return airway 2 and the machine roadway 3. Therefore, when pushing the hydraulic support, it is pushed along the direction of the return airway and the machine roadway, and the hydraulic support will not slide downwards (if the center line of the hydraulic support is perpendicular to the coal wall, after each movement of the hydraulic support, it will move a distance towards the lower outlet. Since the coal mining face is inclined, during the advancement of the coal mining face, it is constantly necessary to add supports from the upper outlet and remove supports from the lower outlet). This reduces or avoids adding hydraulic supports from the upper outlet and removing hydraulic supports from the lower outlet, reducing the workload and improving the coal mining efficiency. This method also reduces or avoids adding conveyor sections from the upper outlet and removing conveyor sections from the lower outlet (because if the hydraulic support moves a distance towards the lower outlet each time it moves, the conveyor will also move a section towards the lower outlet). In the pushing method of the conveyor and the cutting method in this example, they effectively cooperate with the movement of the hydraulic support in the direction parallel to the return airway and the machine roadway. Among them, after the floating coal is collected in the upwards direction, the conveyor is pushed from bottom to top, and the sections of the conveyor will squeeze upwards (at least not squeeze downwards), preventing the conveyor from moving towards the lower outlet direction, so that the conveyor has enough length to form a curved section (if the conveyor moves towards the lower outlet direction, the length in the upper outlet direction is insufficient, and the length required to form a curved section is not enough), and there is no need to lower the conveyor section to the coal mining face for the curved section, reducing the workload.

[0073] The length of the section without hydraulic props at the upper outlet of the coal mining face shall not be greater than 1.5 m. When it is greater than 1.5 m, hydraulic supports shall be added immediately; the length of the section without hydraulic props at the lower outlet shall not be greater than 1.5 m. When it is greater than 1.5 m, hydraulic supports shall be lowered.

[0074] The section without hydraulic props at the lower outlet is supported by single hydraulic props with caps. The row spacing of the single hydraulic props is 0.8 m, the pillar spacing is 0.8 m, the roof control distance is between 4.34 m and 5.14 m, and the caving step distance is 0.8 m.

[0075] Support method for the section without hydraulic props at the lower outlet:

[0076] The pedestrian safety exit sections at the upper outlet and the lower outlet are supported by single hydraulic props with wooden crossbeams. Among them, the specifications of the wooden crossbeams are: length 200 mm, width 100 mm, thickness 50 mm.

[0077] Among them, the density of the single hydraulic props is not less than 0.8 props / m², the row spacing of the single hydraulic props is 0.8 m, and the pillar spacing is 0.8 m.

[0078] A row of inclined dense props is arranged on the side close to the coal wall in the pedestrian safety exit section at the lower outlet, and the pillar spacing of the inclined dense props is 400 mm; a row of strike props is driven at the position close to the top beam of the first support in the pedestrian safety exit section at the lower outlet, and the pillar spacing is 400 mm.

[0079] During the withdrawal support, after the coal mining face advances, when withdrawing the support facilities, first withdraw the strike props, and then withdraw the inclined dense props. Replace props shall be set up before withdrawing the inclined dense props. Protective props must be set up before withdrawal, the retreat route shall be cleared, and the withdrawal shall be carried out in the order from bottom to top, from the goaf to the coal wall, first support and then withdraw, first dense props and then point props. Check the roof before withdrawal. The pillar withdrawing operator shall stand at a safe location above the sidewalk on the side of the new dense props close to the coal wall. Use a withdrawal handle rope with a length greater than 3m for remote withdrawal. When encountering a pillar that is difficult to withdraw, use timber to make a replacement first and then withdraw, and the replacement shall not be withdrawn again. The withdrawal sequence is from bottom to top, from dense props to the coal wall.

Claims

1. The steeply inclined coal seam downward pseudo-inclined mining process is to set up a return air lane and a machine lane with a lower horizontal position than the return air lane in the coal seam, and adopt the backfilling method. The coal mining working face is arranged between the return air lane and the machine lane. The coal mining machine is arranged on the coal mining working face to walk and cut coal, and support facilities are set up on the coal mining working face; The coal mining working face has an upper outlet near the return air lane and a lower outlet near the machine lane; it is characterized in that: Specifically: When the true inclination of the coal seam is more than 70° and the average inclination length is more than 100 meters, the upper outlet of the coal mining face arranged in the coal seam is 15-20 meters ahead of the lower outlet, so that the pseudo inclination of the coal mining face is 62°; At the upper outlet, a feed section with a length of 25m-30m is set, and the feed section is arranged obliquely with the coal mining working face to form an angle of less than 8°; so that the coal mining machine gradually cuts into the coal wall when walking to complete the feed; the first coal cutting feed is 0.8m; The support facilities include support strength greater than 386kN / m 2 Hydraulic support; The top plate of the hydraulic support is parallel to the top plate of the coal mining face, the center line of the hydraulic support is parallel to the return air lane and the machine lane, and the center line of the hydraulic support forms an angle of 78-72° with the coal mining face; The hydraulic support is continuously pushed forward along the direction of the coal mining face during mining to control the roof of the mining section. The maximum roof control distance is 5.64m, the minimum roof control distance is 4.84m, and the roof caving step distance is 0.8m. The hydraulic support pushes the conveyor. When pushing in each coal mining cycle, the conveyor section at the lower end of the coal mining working face is pushed first, and then the remaining conveyor sections are pushed upward step by step; The length of the section without hydraulic support at the exit of the coal mining working face shall not be greater than 1.5m. If it is greater than 1.5m, hydraulic support shall be added immediately; the length of the section without hydraulic support at the lower exit shall not be greater than 1.5m. If it is greater than 1.5m, hydraulic support shall be lowered; The lower exit section without hydraulic props is supported by a single hydraulic prop with a cap, the row spacing of the single hydraulic prop is 0.8m, the column spacing is 0.8m, the top control distance is between 4.34m and 5.14m, and the top release step distance is 0.8m.

2. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: The method of walking and cutting coal by arranging the coal mining machine on the coal mining working face also includes: after completing the feed, cutting the coal downward to the lower outlet, and the downward speed is not more than 3m / minute.

3. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: The support strength of the support facilities is greater than 280kN / m 2 .

4. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: The goaf area after the coal mining face is pushed through is treated by the full collapse method.

5. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: The pedestrian safety exit section at the lower exit is supported by a single hydraulic support with a wooden cantilever board. The specifications of the wooden cantilever board are: 200mm long, 100mm wide, and 50mm thick. The density of a single hydraulic prop is not less than 0.8 per m. 2 The row spacing of single hydraulic supports is 0.8m and the column spacing is 0.8m.

6. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: A row of inclined dense pillars is arranged near the coal wall at the pedestrian safety exit section at the lower exit, with a column spacing of 400mm; The pedestrian safety exit section at the lower exit has a row of walking pillars near the top beam of the first support, with a column spacing of 400mm.

7. The steeply inclined coal seam downward pseudo-inclined mining process according to claim 1, characterized in that: After the coal mining face advances, when withdrawing the support facilities, first withdraw the walking pillars, then withdraw the inclined dense pillars, and before withdrawing the inclined dense pillars, set up the replacement pillars.

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